Duet Ethernet header ext driver 2ma clamp or protect it?
CNCModeller last edited by CNCModeller
I'm planning on using TB6600 external drivers on the header of a Duet Ethernet unless its not appropriate. The TB6600 documentation I can find states that it'll run on 3.3v but it suggest that a 5ma signal is required (in the troubleshooting section).
Normally I'd just give it a go but with the Duet being a higher premium product I didn't want to risk it without checking first. My assumption is that the signal current is clamped to max 2ma and as such connecting a more demanding opto-isolater wont actually do any damage?
I've also reviewed several other threads, unfortunately they are locked and haven't clearly stated if the driver works on the header or not.
One thing I have noted is that the TB6600 ENA input is a stepper disable rather than enable (0v = driver enabled), so for those having issues getting things going I'd suggest that you disconnect (or invert if possible) the ENA signal to the driver.
Any constructive feedback would be gratefully received.
For external stepper drivers with optically isolated inputs, we recommend you use this https://www.duet3d.com/DuetAddons/Expansion_Breakout to boost the voltage and current of the 5 sets of step/dir/enable signals on the expansion connector.